Automatic tension device



E. H. MONKLEY AUTOMATIC TENSION DEVICE June 8, 1954 2 Sheets-She et 1 Filed Oct. 18, 1950 E DNARD. H. llO/YKLl-T-INVENToR.

June 8, 1954 E. H. MONKLEY 2,680,573

AUTOMATIC TENSION DEVICE Filed Oct. 18, 1950 2 Sheets-Sheet 2 9 EDNARDHMONKLEY uvvmmn mfl Patented June 8, 1954 UNITED STATES PATENT OFFICE 2,680,573 AUTOMATIC TENSION DEVICE Edward H. Monkley, Worcester, Mass.

Application October 18, 1950, Serial No. 190,699

This invention relates to new and. improved automatic tension devices particularly adapted to the rolling, unwinding, and re-winding of weblike material such as paper, flexible metal, fabrics, cellophane, plastic materials, etc., on cores or mandrels.

In rolling and re-winding there are many problems involved in the tension to be applied to the web being re-wound. For instance, as the roll increases in size as it takes up the web, it is necessary to increase the torque applied to shaft driving the roll as the radius of the roll being wound increases; and at the sametime it is necessary to reduce the pull, i. e., tension, on the web as the radius of the roll increases because if the tension is maintained the same throughout the winding of the roll, the outside portion of the wound roll stretches during rolling a great deal more than does the web more nearly toward the center of the roll; since the radius increases, each lap or wind is longer than the one preceding it. Due to this, and to the tendency of the material to return to unstretched condition, the material near the center of the roll will be squeezed as the material returns to normal untensioned condition and pressure is exerted by the outer material upon the inner material causing the latter to expand and slide along the core, thus giving an uneven edge on the roll of wound material.

In the case of plastic or rubber web or in fact any material that can stretch, when wound by means of a slip clutch with manual tension control, it is found that the rolls are irregular at their ends, they have hard and soft spots, and the material at the center or near the core is pushed outwardly axially, due to the irregular application of increased friction in the clutch.

It is the primary object of the present invention to provide an automatic tension device which smoothly, gradually and automatically increases the torque on the driving shaft of the roll while accurately controlling the tension on the web; and another object of the invention resides in the provision of an automatic device for maintaining an even tension on a series of webs all being wound on separate cores but on a single mandrel, particularly in cases where the several webs are of different thicknesses and, therefore, increase in diameter on the cores to varying degrees, thus imparting a varying tension in the absence of the use of the prevent invention.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings in which 11 Claims. (01. 242-55) Fig. 1 is a vertical longitudinal section through a device according to the invention;

Fig. 2 is an end view of the clutch and operating means therefor;

Fig. 3 is a section on line 3-3 of Fig. 1;

Fig. 4 is a section on line 4-4 of Fig. 1;

Fig. 5 is an enlarged view of an indicating dial illustrated in Fig. 1;

Fig. 6 is a vertical central section through a modified device;

Fig. 7 is a .plan view of a feed screw releasing means looking in the direction of arrow 1 in Fig. 6;

Fig. 8 is a, section on line 8-8 of Fig. 6;

Fig. 9 is a section through the roll shaft showing one of the driving disks in elevation;

Fig. 10 is a section through the roll shaft illustrating one of the winding cores; and

Fig. 11 is an enlarged section on line ll-ll of Fig. 1.

As shown in Fig. 1, shaft l0 mounted in bearings l2 on any kind of frame desired as at I4, is used to rotate a core or mandrel Hi to wind up a roll l8 from a web. The material being wound may be of any kind, but one of the main purposes of the present invention is to provide a rewinding device for slitting machines, although the invention is not limited thereto. In any case, it will be appreciated that as roll I8 is wound it increases in radius and this requires greater tension on the clutch or shaft to maintain constant tension on the web.

A sprocket or the like 20 is driven by any suitable power means and is keyed to a pair of clutch members 22, 24. These clutch members are provided with radial slip type teeth as at 28 and they engage with like cooperating teeth 23 on cooperating clutch members 30, 32. The clutch members 22, 24 and the sprocket are mounted on rotary and axially movable bearings 34 and, therefore, rotate freely with respect to the sleeve 36 formed integrally or attached securely to clutch member 30, and fixed to shaft ill by means 31. The clutch members are provided with legs 35 arranged at an angle forming blades creating a cooling draft, see Fig. 11. The members 22 and 24 are provided with overhanging annular pockets 39 for catching and retaining centrifugally thrown oil or grease, dirt, etc.

The clutch member 32 is non-rotatively but slidably secured to the sleeve '34 as by key 38 working in a complementary keyway. A spring 43 constantly urges clutch member 32 to the left in Fig. l, disengaging the clutch teeth and releasing members 20, 24.

The clutch member 32 is provided centrally assume thereof with a circular bearing 42 providing a rotating mounting for a head 44 having abutting thereon a screw 46, the latter being provided with an adjusting thumb nut 48. The screw 46 is in mesh with a threaded passage in a boss 60 on a lever 62 pivoted at 64 to a part of the framework i4. The other end of lever 62 is secured to a link 66, this link in turn being pivotally secured to a lever 58 pivoted at 60 to a slide 62, the latter being adjustable by means of a bolt 04 in a slot 66 and capable of being tightened up on the slide.

As the lever 06 is pivoted in counterclockwise direction in Fig. 1, it moves link 66 to the left and lever 52 in a counterclockwise direction, to increasingly press clutch member 82 into firmer engagement with clutch part 24, and clutch part 22 therefore into firmer engagement with clutch part 30. There is always slippage between the clutch members but with increasing roll radius, this slippage increases and greater torque is required to maintain constant speed of the web and tension thereon.

Link 56 is preferably divided into two parts "A and 5818, see Fig. 5, these parts being separated at 68 by a fluid type diaphragm which upon being squeezed between the two parts, increases the pressure in a pipe 10 to register on a dial 12, so that the increase in pressure is measurable thereby.

A gear 14 on shaft I is meshed with a gear 18 on a shaft 18 in a box 80, the shaft 18 being provided with a worm 82, in mesh with a worm gear 84, see Fig. 8, so that as shaft I0 rotates, the gear 84 is rotated proportionally thereto. Gear 84 is mounted on an upright sleeve 86 journalled at 88 in the box 80 and this sleeve is provided with a pair of diametrically opposed interior slots 80 into which are received the ends of a pin 82 diametrically disposed in a screw 94. The screw 84 extends upwardly out of the box 80 and terminates in a swivel yoke Journalling a roller 66. This roller rides against a fixed plate 88 and as it rises moves lever 68 counterclockwise. Lever 68 and plate 88 are undercut or grooved to accommodate the roller, see I00, Fig. 4.

As shaft I0 rotates, the screw 84 is rotated also and being in mesh with a nut or the like I02, is caused to advance in an upward direction thus clearly moving the lever 06 in a counterclockwise direction as in Fig. 1.

The nut I02 is in two parts I02A and I 023, see Fig. 7, each part being provided with a leg I04, I06 in mesh with a gear I08 turnable by means of a handle IIO to separate the two parts of the nut and release the screw 84. By this means the screw may be quickly and easily returned to its lowermost position, the two halves of the nut acting as a clutch and riding in guideways H2 in the top of the box 80.

It will be seen that by this construction .the torque on the shaft I0 is increased proportionally to increase in radius of the roll I81 as it rotates; and furthermore, this relationship is adjustable for materials of different thickness by means of plate 62 which may be shifted to vary the initial angularity of lever 88.

It is, of course, to be understood that the parts are so arranged that when the power is first turned on shaft I0 will rotate but with some slippage as the roll increases in diameter, the slippage increases. Manual adjustment of the torque is necessarily erratic or in steps, and this clearly causes hard and soft spots in the roll and makes the web drift. As increase in torque is required on fixed plate I54 and moving a lever I68 counter- I by expanding radius of roll I8, the torque is proportionally increased by the present invention by the gradually greater pressure exerted to the right on clutch part 32 by means of the novel structure described.

Referring now to Fig. 6, there is shown a shaft I20 driven by a sprocket or other driver I22 and mounted in bearings I24 in a frame or other support I26. This shaft drives a mandrel I28 on which is mounted a plurality of individual cores I30. These cores are ordinarily made of paper and they are not secured to the mandrel I28. Each core forms a base for rolling or winding a narrow web thereon as at I82, I84, I86, etc. It is pointed out that even though the individual webs should be slit from a single large roll, nevertheless, the thickness thereof will vary and thus certain of the individual rolls will increase in diameter quicker than others, thereby creating a varied tension on the individual rolls. The modification of the device shown in Fig. 6 automatically renders the tension uniform.

A gear I38 is in mesh with a gear I40, the latter being mounted on a shaft I42 having a worm on it engaged with a worm wheel I44 mounted on a sleeve I46. A screw I48 is slidably but nonrotatably mounted with respect to sleeve I46, and supports a relatively rotatable yoke I60 and roller I52. This mechanism is the same as that shown at Fig. 8, Fig. 7 and Fig. 1. As shaft I20 is rotated, the screw I48 rises with roller I62 riding clockwise on a plate I 68. This action moves a link I80 to the left and a lever I62 pivoted at I64 in a counterclockwise direction. Lever I62 terminates in a roller I00 bearing on a washer I68, the latter being disposed about mandrel I28 and spring pressed toward the lever against roller I86 by a spring I10. The spring I10 finds its other reaction point against a washer I12 which has an inwardly directed lug 14 in groove I 16 in the mandrel I28. There is a washer I12 between each core I80 and all of these washers are, therefore, driven by the mandrel. As the shaft rotates, winding the webs on the cores, the pressure on spring I10 is gradually proportionally increased, thus creating a greater and greater driving friction between the various washers I12 and the cores I80 so that the latter are rotated with greater torque applied.

This invention applies also to the unwinding roll as well as the winding roll, as the two rolls both must be controlled to avoid piles, flapping, or sag of the web between the unwinding and the re-winding rolls.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is:

1. Device of the class described comprising a roll winding element, means to rotate the same to wind or unwind a web, including a rotary shaft, and means independent of the web and out of contact therewith for automatically controlling the torque applied to the shaft, said means comprising a movable member, means connected to the shaft to move the member constantly as the shaft rotates, a linkage moved by the movable member, a slip clutch having a part thereon on the shaft and another part adapted to be driven, means constantly tending to separate the clutch parts, said linkage bearing on the driven clutch part to force the parts toward each other to an increasingly greater extent as the shaft continues rotation thereof, said linkage including a pivoted lever arranged at an angle to the path of the movable member.

2. Device of the class described comprising a roll winding element, means to rotate the same to wind or unwind a web, including a rotary shaft, and means independent of the web and out of contact therewith for automatically controlling the torque applied to said shaft, said means comprising a movable member, means on the shaft to move the member constantly as the shaft rotates, a linkage moved by the movable member, a slip clutch having a part thereon on the shaft and another part adapted to be driven, means constantly tending to separate the clutch parts, said linkage bearing on the driven clutch part to force the parts toward each other to an increasingly greater extent as the shaft continues rotation thereof, said linkage including a pivoted lever arranged at an angle to the path of the movable member, and means to adjust the angularity of the lever relative to said path.

3. Device of the class described comprising a roll winding element, means to rotate the same to wind or unwind a web, including a rotary shaft, and means independent of the web and out of contact therewith for automatically controlling the torque applied to said shaft, said means comprising a pivoted lever, means to pivot the lever, a movable member operatively connected to the shaft to advance to pivot the lever, a linkage effective to be moved by the lever according to the rotation of the shaft, means to increase torque on the shaft, said last named means comprising a slip clutch, the linkage bearing on the latter to increase the friction thereof as the shaft rotates, said lever pivoting means including an axially movable screw, and a nut for the screw, and means to rotate the screw from the shaft.

4. The device of claim 3 wherein the nut comprises a plurality of parts, and means to separate the nut parts to release the screw.

5. A device of the class described comprising a roll winding element, means to rotate the same to wind or unwind a web, including a shaft, a series of washers axially slidable but non-rotatably mounted on the shaft, cores on the shaft alternating with the washers, means to impart axial pressure on the washers and cores to cause the latter to rotate, and means independent of the web and out of contact therewith designed to constantly increase the pressure as the shaft rotates to increase the driving torque on the cores, said last named means comprising a lever having an end bearing on a washer, means to pivot the lever to increase the bearing pressure, and means actuating the lever pivoting means and driven from the shaft;

6. Roll tension control device comprising a shaft, a roll to be driven on the shaft, a driving element rotatably mounted with respect to the shaft, a pair of oppositely directed outwardly facing slip clutch elements fixed with relation to the driving element, a sleeve on the shaft in fixed relation thereto, a slip clutch element fixed to the sleeve and cooperating with one of the outwardly facing clutch elements, another slip clutch element axially slidable but non-rotatable on the sleeve and cooperating with the other of said outwardly facing clutch elements, said driving element being capable of axial movement relative to the shaft, means resiliently tending to separate the first-named pair of clutch elements from the second-named sleeve mounted clutch element, means to gradually move the clutch elements into even greater driving contact, said means comprising an element bearing on the axially movable sleeve mounted clutch element and means pressing the same toward the firstnamed pair of slip clutch elements and in turn pressing the latter toward the fixed-relation sleeve mounted clutch element, said means being actuated by the shaft.

7. Roll tension control device comprising a shaft, a. roll to be driven on the shaft, a driving element rotatably mounted with respect to the shaft, a pair of oppositely directed outwardly facing slip clutch elements fixed with relation to the driving element, a sleeve on the shaft in fixed relation thereto, a slip clutch element fixed to the sleeve and cooperating with one of the outwardly facing clutch elements, another slip clutch element axially slidable but non-rotatable on the sleeve and cooperating with the other of said outwardly facing clutch elements, said driving element being capable of axial movement relative to the shaft, means resiliently tending to separate the first-named pair of clutch elements from the second-named sleeve mounted clutch element, means to gradually move the clutch elements into even greater driving contact, said mean comprising an element bearing on the axially movable sleeve mounted clutch element and means pressing the same toward the first-named pair of slip clutch elements and in turn pressing the latter toward the fixed-relation sleeve mounted clutch element, said element pressing means including a fixed nut, a threaded member in mesh with the nut, means to rotate the threaded member to advance the same relative to the nut, a connection between the shaft and the threaded member to rotate the latter as the shaft is driven, and means actuated by the threaded member to increase pressure on the element bearing on the axially movable sleeve mounted clutch element.

8. Roll tension control device comprising a roll to be driven, a driven shaft to rotate the roll, a threaded member, a fixed nut for the latter so that the member advances as it is rotated, means on the shaft to rotate the threaded member as the shaft rotates, a lever mounted to be angularly swung by the threaded member as the latter advances, a driving element mounted for relative rotational and axial movement with respect to the shaft, a slip clutch element on the driving element, a slip clutch element fixed to the shaft and cooperating with one of said first-named clutch elements, another slip clutch element axially movable on but non-rotational with respect to the shaft and cooperating with the other of the first-named clutch elements, spring means urging the cooperating clutch elements apart, said lever being effective to gradually force the cooperating clutch elements together as the shaft turns, regardless of the rotation of the driving element.

9. Roll tension control device comprising a roll to be driven, a driven shaft to rotate the roll, a threaded member, a fixed nut for the latter so that the member advances as it is rotated, means on the shaft to rotate the threaded member as the shaft rotates, a lever mounted to be angularly swung by the threaded member as the latter advances, a driving element mounted for relative rotational movement with respect to the shaft, slip clutch elements on th driving element, another slip clutch element axially movable on but 7 non-rotational with respect to the shaft and cooperating with the first-named clutch element, spring means urging the cooperating clutch elements apart, said lever being eflective to gradually force the cooperating clutch elements together as the shaft turns, regardless of the rotation of the driving element.

10. Roll tension control device comprising a roll to be driven, a driven shaft to rotate the roll, a threaded member, a fixed nut for the latter so that the member advances as it is rotated, means on the shaft to rotate the threaded member as the shaft rotates, a lever mounted to be angularly swung by the threaded member as th latter advances, a driving element mounted for relative rotation and axial movement with respect to the shaft, a slip clutch element on the driving element, a slip clutch element fixed to the shaft and cooperating with one of said firstnamed clutch elements, another slip clutch element axially movable on but non-rotational with respect to the shaft and cooperating with the other of the first-named clutch elements, spring means urging the cooperating clutch elements apart, said lever being effective to gradually force the cooperating clutch elements together as the shaft turns, regardless of the rotation of the driving element, said lever bearing on the axially movable clutch element that is non-rotational on th shaft, and said spring means being arranged against and between the last referred to clutch element and the driving element, and a sleeve mounting for the latter, the shaft-fixed clutch element being on the sleeve and the sleeve being fixed to the shaft, the driving element being journalled on the sleeve and a stop on the sleeve preventing axial movement of the driving element thereon in one direction only.

11. Device of the class described comprising a roll winding element, means to rotate the same to wind or unwind a web, including a rotary shaft, and means independent of the web and out of contact therewith for automatically controlling the torque applied to said shaft, said means comprising a movable member, means on the shaft to advance the member constantly as the shaft rotates, a linkage moved by the movable member, a slip clutch having a part thereof on the shaft and another part adapted to be driven, means constantly tending to separate the clutch parts, said linkage bearing on the center of rotation of the driven clutch part to force the parts toward each other to an increasingly greater extent as the shaft continues rotation thereof, and a pressure indicator in the linkage to measure the degree of thrust on the clutch parts.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 667,474 Wilson Feb. 5, 1901 1,654,800 Ga-rbutt Jan. 3, 1928 1,849,383 Richardson et a1. Mar. 15, 1932 1,944,916 Beaver et al. Jan. 30, 1934 1,974,126 Spillane Sept. 18, 1934 2,200,328 (John et a1. May 14, 1940 2,252,419 Slaughter Aug. 12, 1941 2,361,192 Goodwin Oct. 24, 1944 2,462,766 Olson et a1. Feb. 22, 1949 FOREIGN PATENTS Number Country Date 229,561 Germany May 7, 1909 225,247 Germany June 2, 1909 12,209 Great Britain Aug. 24, 1915 319,201 Great Britain Jan. 16, 1930 

